\documentclass[10pt]{beamer}
\usepackage{beamerthemesplit}
\usepackage{graphicx}
\usepackage{color}
\definecolor{dbluecolor}{rgb}{0,0,0.6}
\definecolor{dredcolor}{rgb}{.5,0.0,0.0}
\definecolor{dgreencolor}{rgb}{0,0.4,0}
\newcommand{\dred}{\color{dredcolor}\bf}
\newcommand{\dblue}{\color{dbluecolor}\bf}
\newcommand{\dgreen}{\color{dgreencolor}\bf}
\newcommand{\bc}[1]{\color{dbluecolor}\tt{#1}}


\begin{document}
%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=8cm,height=6cm]{polar.png}
\end{figure}
\end{center}
}

%%%

%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=7cm,height=5cm]{polar.png}
\end{figure}
\end{center}
}

%%%
%%%

\frame
{
\begin{center}
\begin{figure}
\includegraphics[width=3.5in,height=2.5in]{zeta.png}
\end{figure}
\end{center}
}

%%%
%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=6cm,height=6cm]{spiral.png}
\end{figure}
\end{center}
}

%%%

%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=5cm,height=5cm]{spiral.png}
\end{figure}
\end{center}
}

%%%
%%%

\frame
{
\begin{center}
\begin{figure}
\includegraphics[width=3in,height=3in]{spiral.png}
\end{figure}
\end{center}
}

%%%
%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=8cm,height=6cm]{array.png}
\end{figure}
\end{center}
}

%%%

%%%

\frame
{
\begin{center}
\begin{figure}[hbp]
\includegraphics[width=4in,height=3in]{array.png}
\end{figure}
\end{center}
}

%%%



\end{document}